Ball-caster.



Patented Dec. 4, |900. W. H. FAUBER.

BALL CASTER.

(Applicltion led Aug. 5, 1899.)

No. ("0v Model.)

WMM

Nrrnn STATES ATENT Fine fr.

BALL-CASTER.

SPECIFICATION forming pere ef Letters recent Ne. 663,164, dated December4., 1900.

Application led August 5.1899. Serial No. 726,273. KNO model.)

T0 a/ZZ wwnt t may concern:

Beit known that I, WILLIAM H. FAUBER, of Chicago, in the county of Cookand State of Illinois, have invented certain new and useful Improvementsin Ball-Casters; and I do hereby declare that the following isa full,clear, and exact description thereof, reference beine; had to theaccompanying drawings, and to the letters of reference Vmarked thereon,which form a part of this specification.

This invention relates to improvements in ballcasters wherein one of thebearing members is formed by a spherical rotative element andantifriction-balls are interposed between the rotative element and theother bearing-surface.

The invention is shown as embodied in a furniture-caster; but it may beotherwise embodied where a bearing of this character is desired.

The invention consists in the matters hereinafter set forth, and moreparticularly pointed out in the appended claims.

In the drawings, Figure l is a side eleva tion of a caster made inaccordance with my invention. Fig. 2 is an axial section thereof. Fig. 3is a horizontal section taken on line 3 3 of Fig. 2, showing in bottomplan View the arrangement of the antifriction-balls. Figs. 4 and 5 arebottom and top plan views, respectively, of the shifting gud e-platewhich is interposed between the supporting-roller and thebearing-surface of the casing and in which guide-grooves or races forthe'antfrictionballs are formed. Fig. 6 is a horizontal section of thecasing, showing in bottom plan view the bearing-surface therein. Fig. 7is an axial section of a modified form of a caster. Fig. 8 is a bottomplan View of the shifting guide-plate used therein.' Fig. 9 shows a partof such plate removed from the other parts thereof.

As shown in said drawings, A designates a casing which is open at itslower end and is provided interiorly in its upper part with abearing-surface or cupo, which is shown as projecting slightly below theinner face of the upper wall of the casing, and at its upper end with anexterior screw-threaded shank A, by means of which it may be attached toan article` of furniture. B designates a 4which the supporting-ballrests.

spherical supporting-roller which is contained loosely within saidcasingand protrudes at its lower part from the open end of said casing,so that it may rest in contact with a supe portingf-surface.`

C designates a guide-plate which is interposed between thesupporting-roller and the upper wall of the casing, said plate havingthe general form of 'a segment of a hollow sphere, so as to conform tothe adjacent surfaces of the cup ct and supporting-roller.

D D designate a plurality of antifrictionballs which are adapted totransmit to the supporting-roller the weight brought on the casing.

The plate C is constructed to provide endless guide-grooves or races,within which the balls are seated and which serve to hold said balls inproper position with respect to the cup of, and supporting-roller, andis adapted to be moved or shifted, so as to change the position of theguide-grooves or races therein in accordance with the direction oftravel of the caster over its supporting surface on One guidegroove orrace is provided on each side of the center of said plate,and eachguide-groove consists of a substantially straight portion c and a curvedportion c', giving thereto approximately the form of the letter D. Saidsubstantially straight portions c of said grooves or races are locatedbetween the curved portions thereof and the center of the plate and aresubstantially parallel with each other, while the curved portions of thegrooves are "located adjacent to the outer margin of the plate.

Said parallel portion c of the guide-groovesl -upper walls of saidgrooves and serve to hold the plate out of contact with the supporting!roller. Said antifrictionballs are made of greater diameter than thethickness of the plate, so that the balls which occupy the straightportions c of the guide-grooves or races extend beyond both the upperand lower sustained by the caster, the remaining balls; sustainingonly'the Weight of the plate C.

Said plate is connected with the casing in such manner that it may beshifted or rotated about its central axis, whereby the portions c of theguide-grooves or races may be always parallel with the line of movementof the caster, and therefore parallel with the plane of rotation of thesupporting-roller. As herein shown, said 'plate is provided with acentral aperture c2, which is loosely engaged by a pin a', whichprojects downwardly from the bearing-surface of the cup a centrallythereof.

The lower margin of the casing may be crimped inwardly, as shown, tohold the supporting-roller properly7 in place, as when the caster isbeing handled or when it is lifted away from its supporting-surface.

The operation of the caster may be readily understood from the foregoingdescription. When weight is brought upon the caster and it is caused tomove in a manner to rotate the supporting-roller, the antifriction-ballsD being in contactwith the cup a, and with the supporting-roller saidballs roll or travel between the supporting-roller and the cup andthrough the endless guide-grooves or races. When the direction ofmovement of the caster, and therefore the direction of rotation of thesupporting-roller, is changed, the pivotal connection of the guide-platewith the casing permits said plate to be shifted or turn about the pind', so as to bring the portions c of the guide-grooves or races parallelwith the new plane of rotation of the supporting-roller, after which theoperation of the device is the same as before. Such turning or shiftingof the platenecessarily takes place, because if the supportingroller beturned when the straight parts c of the guide-grooves are at an angle ortransverse with respect to the plane of rotation of thesupporting-roller the balls D in rolling between the supportingrollerand cup a will be carried against and exert pressure upon the sides ofthe guidegrooves in the guide-plate in such manner as to turn or shiftsaid plate until the straight parts c are again parallel with the planeof rotation of the supporting-roller. Those of the antifriction-balls Dwhich are at any time beneath or in contact with the cup ct, and whichtherefore receive the Weight brought on the caster, being free to movein a path parallel with the plane of rotation of the supporting-roller,and which is the path of least resistance, the friction between saidparts is reduced to a minimum and the supportingroller may freelyrotate.

The provision of the shifting guide-plate C, constructed and arranged inthe manner described, is an important feature of my invention, as itenables the path of movement of those of the balls Vwhich are in theiractive or operative position to be maintained parallel kwith the planeof rotation of the supportingroller and prevents said antifriction-ballsbeing pressed against the side walls of the races o rguide-grooves,which would result in increased friction and impair the efciency of thecaster.

In Figs. 7, 8, and 9. is shown a modified form of the caster. In saidfigures the casing A and the supporting-roller B are made substantiallyas shown in the previous igures. The antifriction-balls are alsoarranged in the same manner as before described. In this instance,however, the caster is provided with a shifting guide-plate E, which,though performing the same function as the similar part of thepreviously-described construction, is made of a slightly-modifiedconstruction. In this instance said plate is provided on each side ofits center vwith oblong openings E', which are divided by a central parte, and Within said openings are contained loose or floating pieces E2,which are made of the same shape as the openings, but smaller than thesaine, thereby providing between said floating pieces and the main bodyof the plate endless ball-races or guide-grooves compris- -,ing parallelportions e e and curved portions e2 e2. The part e of said plate isprovided with an aperture e3, which is adapted for engagement with adepending pin a2, and by means of which said plate 'may be shifted orturned about its center to bring the antifriction-balls which occupy theparallel portions of the races in a plane parallel with the plane ofrotation of the supporting-roller B. The part of the interior surface ofthe upper wall of the casing located immediately above the outer orcurved portion of the ball-races is not concentric with thebearing-surface a3, which is engaged by the balls in the portions of theraces nearest the center of the plate, but is more widely separated fromthe supporting-roller than such part d3, so that the balls occupying thesaid curved portions of Vthe races are out of contact with said upperWall of the casing. As in the prior construction, the supporting-ballsare made of such diameter as to extend beyond the upper and lowersurfaces of the plate, so that when occupying the portions e of theguide-grooves or races they will be in contact with thesupporting-roller and 'the bearing-surface a3 and in position totransmit Weight from 'the casing to the supporting-roller. Said groovesare made of a width slightly greater than the diameter of the balls, sothat said balls may pass freely therethrough. As the curved portions of'the grooves in this construction extend entirely through the plate,said plate is not supported on the antifriction-balls, as in IIO theprior construction, but rests directly upon the upper surface of thesupporting-roller. The operation of this form of device is obviously thesame as that of the previouslydescribed construction.

I claim as my inventionl. A ball-caster comprising a part having aconcave bearing-surface, a spherical body, a plurality ofantifriction-balls, and a gener-A ally horizontal plate between saidbody and concave bearing-surface provided with two endless races for theballs, one on each side of the center of said plate, and the adjacentparts of which races extend through the plate and are generally parallelwith each other and with the plane of rotation of the sperical body, thepart of the concave bearing-surface adjacent to the parallel portions ofthe races being located at a distance from the spherical body, when thecaster is in its operative position, equal to the diameter of theantifriction-balls, and the remaining portions of the spherical body andthe concave bearing-surface being located at a greater distance apart.

2. A ball-caster comprising a part having a concave bearingsurface, aspherical body, antifriction-balls, and a shifting guide-plate for saidantifriction balls, constructed to guide the balls successively awayfrom and toward the -space between the spherical and concavebearing-surfaces.

3. A ball-caster comprising a part having a, concave bearing-surface, aspherical body, antifriction-balls, and a shifting guide-plate locatedbetween said body and the bearingsurface provided with an endless raceor guidegroove for said balls, a part of which groove extends throughthe plate.

4. A ball-caster comprising a part having a concave bearing-surface,aspherical body,two sets of antifriction-balls, and a rotating guideplatepivoted to said part concentrically of said bearing-surface, andprovided with two grooves or races within which said balls travel, oneof said grooves being located on each side of the center of the plate.

5. A ball-caster comprising a part having a concave bearing-surface, aspherical body, antifriction-balls, and a shifting guide-plateinterposed between said bearing-surface and spherical body, and providedwith an endless race within which said balls are seated, a portion ofsaid race having its sides located in parallel planes and acting toguide the balls in a path parallel with the plane of rotation of thespherical body.

6. A ball-caster comprising a part having a concave bearingsurface, aspherical body and antifriction-balls, of a shifting guide interposedbetween said bearing-surface and spherical body, and provided with twoendless races within which said balls are seated, portions of said racesbeing parallel with each other and adapted to guide the balls inparallel paths across said concave bearing-surface.

7. A ball-caster comprising a part having a concave bearing-surface, aspherical body, antifriction-balls, a shifting guide-plate between saidbody and bearing-surface provided with a guide-groove or ball-racehaving parallel side walls which extend therethrough and within whichsaid antifriction-balls travel, said balls having a diameter greaterthan the thickness of the said plate.

8. A ballvcaster comprising a part provided with a concavebearing-surface, a spherical body, two sets of antifriction-balls, aguideplate between said body and the bearing-surface which is rotativelymounted on a pin which projects from said bearing-surface,said platebeing provided at each side of the center thereof with an endlessgrooveor race in which said antifriction-bails travel, and the balls onlywhich at a given time occupy the adjacent parts of the grooves receivingthe weight brought upon the caster.

9. A ball-caster, comprising apart provided with a concavebearing-surface, a spherical body, two sets of antifriction-ballsbetween said spherical body and the bearing-surface, and a rotativeplate interposed between said supporting-roller and bearing-surfacewhich is provided with two endless guide-grooves or races, within whichsaid balls travel, the parts of said grooves adjacent to the center ofthe plate being parallel with each other and adapted to guide the ballsin parallel paths across said concave surface.

In testimony that I claim the foregoing as my invention I affix mysignature, in presence of two witnesses, this 3d day of August, A. D.

WILLIAM H. FAUBER.

Witnesses: C. CLARENCE POOLE,

WILLIAM L. HALL.

IOO

